Printing method and printing apparatus

Abstract

A printing method for performing printing while complementing black with composite black, the printing method including: printing a test pattern having a plurality of patch images for which composite mode varies, this test pattern being printed for each dot size of the black to be complemented; causing a user to select a desired patch image from among the plurality of the patch images included in the printed test pattern, the selection being made for each of the dot size of the black ink to be complemented; and performing printing while complementing the black to be complemented with the composite black generated on a basis of the composite mode corresponding to the desired patch image selected correspondingly to the dot size of the black ink to be complemented.

What is claimed is: 
     
       1. A printing method for printing a print image using a plurality of dots formed by discharging, by a printing head, an ink droplet on a printing medium while relatively moving the printing head and the printing medium in a relative movement direction, the printing head being configured to discharge, on the printing medium, a black ink and inks of a plurality of colors each as the ink droplet, the printing method comprising:
 a test pattern printing step of printing a test pattern having a plurality of patch images using different composite mode for each of the dot sizes of the black ink to be complemented, the composite mode being a combination of a dot size of each of the inks of the plurality of colors used to generate composite black that complements the black, the composite black being obtained by combining ink droplets of the discharged inks of the plurality of colors; 
 automatic selection step of capturing the printed test pattern as image data, and selecting, as a desired patch image, a patch image for which a difference in color between the black and the composite black is determined to be minimum by image processing, the selection being made from among the plurality of patch images included in the printed test pattern, the selection being made for each of the dot sizes of the black ink to be complemented; and 
 a printing step of performing printing while complementing the black to be complemented with the composite black generated on a basis of the composite mode corresponding to the desired patch image selected correspondingly to the dot size of the black ink to be complemented. 
 
     
     
       2. The printing method according  claim 1 , wherein
 printing is performed while complementing, with the composite black, a dot-missing pixel occurring when part of a plurality of nozzles of the printing head that discharge an ink droplet of the black ink have discharge defect, and 
 the patch images printed in the test pattern printing step is a print image including a first print image and a second print image that are alternately arranged in a direction intersecting the relative movement direction, the first print image including dots of the black ink and including a plurality of dot rows extending in the relative movement direction, the second print image including the composite black and including a complementary pixel row extending in the relative movement direction. 
 
     
     
       3. The printing method according to  claim 2 , wherein
 the printing head is configured to form a dot having a small size and a dot having a middle size greater than the small size, for each of the black ink and the inks of the plurality of colors, 
 the inks of the plurality of colors for generating the composite black include a cyan-based ink, a magenta-based ink, and a yellow-based ink, 
 the test pattern includes a first test pattern when the dot size of the black ink to be complemented has the small size, and a second test pattern when the dot size of the black ink to be complemented has the middle size, 
 the first test pattern includes: 
 the patch image including: 
 the first print image including the dot of the black ink having the small size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of the cyan-based ink, the magenta-based ink, and the yellow-based ink all have the small size; and 
 the patch image including: 
 the first print image including the dot of the black ink having the small size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of two inks from among the cyan-based ink, the magenta-based ink, and the yellow-based ink have the small size, and a dot size of a remaining one ink has the middle size, and 
 the second test pattern includes: 
 the patch image including: 
 the first print image including the dot of the black ink having the middle size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of the cyan-based ink, the magenta-based ink, and the yellow-based ink all have the middle size; and 
 the patch image including: 
 the first print image including the dot of the black ink having the middle size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of two inks from among the cyan-based ink, the magenta-based ink, and the yellow-based ink have the middle size, and a dot size of a remaining one ink has the small size. 
 
     
     
       4. The printing method according to  claim 2 , wherein
 the printing head is configured to form a dot having a small size, a dot having a middle size greater than the small size, and a dot having a large size greater than the middle size, for each of the black ink and the inks of the plurality of colors, 
 the inks of the plurality of colors for generating the composite black include a cyan-based ink, a magenta-based ink, and a yellow-based ink, 
 the test pattern includes a first test pattern when the dot size of the black ink to be complemented has the small size, a second test pattern when the dot size of the black ink to be complemented has the middle size, and a third test pattern when the dot size of the black ink to be complemented has the large size, 
 the first test pattern includes: 
 the patch image including: 
 the first print image including the dot of the black ink having the small size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of the cyan-based ink, the magenta-based ink, and the yellow-based ink all have the small size; and 
 the patch image including: 
 the first print image including the dot of the black ink having the small size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of two inks from among the cyan-based ink, the magenta-based ink, and the yellow-based ink have the small size, and a dot size of a remaining one ink has the middle size or the large size, 
 the second test pattern includes: 
 the patch image including: 
 the first print image including the dot of the black ink having the middle size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of the cyan-based ink, the magenta-based ink, and the yellow-based ink all have the middle size; and 
 the patch image including: 
 the first print image including the dot of the black ink having the middle size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of two inks from among the cyan-based ink, the magenta-based ink, and the yellow-based ink have the middle size, and a dot size of a remaining one ink has the small size or the large size, and 
 the third test pattern includes: 
 the patch image including: 
 the first print image including the dot of the black ink having the large size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of the cyan-based ink, the magenta-based ink, and the yellow-based ink all have the large size; and 
 the patch image including: 
 the first print image including the dot of the black ink having the large size; and 
 the second print image including the composite black generated using the composite mode in which dot sizes of two inks from among the cyan-based ink, the magenta-based ink, and the yellow-based ink have the large size, and a dot size of a remaining one ink has the middle size or the small size. 
 
     
     
       5. The printing method according to  claim 2 , wherein
 in the test pattern printing step, the patch images are printed so as to be arranged in one line in the relative movement direction, and 
 the second print image in each of the patch images arranged in one line is printed at a same position in a direction intersecting the relative movement direction. 
 
     
     
       6. The printing method according to  claim 2 , comprising:
 before the test pattern printing step, a test pattern inputting step in which a setting of at least one of the composite mode, an alignment of the patch images, and an arrangement of the first print image and the second print image in the patch image is capable of inputting as a setting of a printing parameter for the test pattern.